Heat carrier and method for the production thereof

Abstract

The invention relates to a heat carrier comprising at least one collector pipe ( 1 ) for receiving the ends of flat pipes ( 10 a ), especially for a CO 2 air conditioning unit for motor vehicles. The collector pipe ( 1 ) is formed by an open hollow profiled section ( 7 ) with edges ( 8, 9 ) forming a continuous longitudinal slit extending in a longitudinal direction and the ends of the flat pipes ( 10 a ), which are twisted at an angle of 90°, are received in a fluidically tight manner in the longitudinal slot. According to the invention, the edges ( 8,9 ) partially abut, forming a separating joint ( 4 ) and are partially rolled back, forming receiving openings for the ends of the flat pipes ( 10 a ). The receiving openings are produced by plastic deformation.

1 . A heat exchanger, with at least one header tube ( 1 ) for the reception of flat tube ends ( 10   a ), in particular for a CO2 air-conditioning system for motor vehicles, the header tube ( 1 ) being formed from an open hollow profile ( 7 ) with edges ( 8 ,  9 ) running in the longitudinal direction and forming a continuous longitudinal slot, and the flat tube ends ( 10   a ) being received in a fluidtight manner in the longitudinal slot, characterized in that the edges ( 8 ,  9 ) butt against one another in regions so as to form a parting joint ( 4 ) and are set back in regions so as to form reception orifices ( 5 ) for the flat tube ends ( 10   a ).  
   
   
       2 . The heat exchanger as claimed in  claim 1 , characterized in that the reception orifices ( 5 ) are produced by the noncutting deformation of the edges ( 8 ,  9 ).  
   
   
       3 . The heat exchanger as claimed in  claim 2 , characterized in that the deformation takes place by means of material displacement.  
   
   
       4 . The heat exchanger as claimed in  claim 1 , characterized in that the edges ( 8 ,  9 ) are prolonged outward beyond the parting joint ( 4 ) and form set-out edge strips ( 2 ,  3 ).  
   
   
       5 . The heat exchanger as claimed in  claim 4 , characterized in that the edge strips ( 2 ,  3 ) are set out in a V-like manner.  
   
   
       6 . The heat exchanger as claimed in  claim 4 , characterized in that the cross section of the header tube ( 1 ) with edges ( 8 ,  9 ) and with edge strips ( 2 ′,  3 ′) corresponds to the shape of an omega (edge strips  2 ′,  3 ′ in a common plane).  
   
   
       7 . The heat exchanger as claimed in  claim 4 , characterized in that the edge strips ( 2 ,  3 ) are designed as the limitation of a depth of insertion of twisted flat tube ends.  
   
   
       8 . A method for the production of a heat exchanger as claimed in  claim 1 , characterized by the following method steps: 
 the initial material used is a plane sheet metal strip ( 6 ) with a relatively large thickness s and with rectilinear edges ( 8 ,  9 ),    the sheet metal strip ( 6 ) is deformed into an open hollow profile ( 7 ) with a longitudinal slot ( 4 ), the edges ( 8 ,  9 ) of the hollow profile ( 7 ) touching one another in the region of the longitudinal slot, and the edge strips ( 3 ,  4 ) being set out as an introduction slope,    the hollow profile ( 7 ) is received in a tool ( 20 ) and supported outwardly,    the reception orifices ( 5 ) are produced in the region of the longitudinal slot ( 4 ) by material displacement (plastic deformation) by means of the introduction of a wedge-shaped tool ( 25 ).    
   
   
       9 . The method as claimed in  claim 8 , characterized in that the flat tube ends ( 10   a ) are introduced into the reception orifices ( 5 ), the hollow profile ( 7 ) being capable of springing open elastically, and in that the header tube ( 1 ) is soldered in a leaktight manner in the region of the longitudinal slot ( 4 ) between the flat tube ends ( 10   a ) and around the flat tube ends ( 10   a ).  
   
   
       10 . The method as claimed in  claim 8 , characterized in that the sheet metal strip ( 6 ) and/or the flat tube end ( 10   a ) are solder-plated at least on one side.  
   
   
       11 . The method as claimed in  claim 8 , characterized in that the sheet metal strip ( 6 ) and/or the flat tube end ( 10   a ) are solder-plated on both sides.